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s s w. McKEE 1 AUTOMATIC TEMPERATURE CONTROL run cAs runmczs Am) mg LIKE. APPLICATION FILED DEC. IBJQI]. 1311 2, 63 9, Patented Aug. 12, I919 Z2 2 SHEETS'SHEET I.

' mill! (if lmumuiwfi THE GAS FURNACES AND CV18- APPLICATION FILED DE Patented Aug. 12, 1919 2 SHEETS-SHEET 2.

GARHET'W; MCKEE. F ROCKFORD, ILLINOIS.

AUTOMATIC TEMPERATURE CONT ROL FOR GAS-FURNACES AND THE LIKE.

To all whom it may concern 'Be it known that I, Gnusrrr W. Molina, a subject of the Kin of Great Britain. residing at Rockford, 1n the county of vviniu bago and State of Illinois, have invented certain new and useful Improvements in Automatic Temperature Controls for Gas Furnaees and the like, of which the follow trolling the temperature of big is a specification.

This invention relates in general to appamtus for automatically regulating and conas burning furnaces, forges, boilers and tie like, and has more specific reference to an apparatus for automatically increasing or diminishing the fiow of oombustive mixture so to maintain at-thepoint of combustion a predetermined and uniform temperature. ()ne of the advantageous features of my invention resides in the provision of an :iplhtlu tus which is simple 1n construction, vheap to manufacture and is extremelv reliahle and accurate in its" operation.

' These advantages are secured in my in vention by utilizmg the pressure of the g..- from the city main as a motive power to actuate an a paratus which automatically increases or iminishes the flow of air and gas to the proportional mixer.

r 'In order to facilitate an understandin of my invention, I have illustrated one preferred embodiment thereof on the :ureompan ing drawings which should be considfire In connection with the followlng de- Sori tion. On the drawings,-

figure 1 is a plan view of an apparatus embodying my invention; A

Fig. 2 is a, side elevation thereof, certain parts being shown in section;

Fig. 3 is an enlarged end view of a mixing valve employed in the apparatus;

f Fig.4 is a longitudinal sectional view through the mixing valve taken suhstan-- tially on the line H of Fig. 3; and

:Flg. 5 is a. cross-sectional view througl'i the mixing valve taken on the line 5--5'of Fig. 4.

By reference to the drawings it will be observed that the apparatus vomprises. primaril'y, a base, 3. upon which is mounted a. mixer 4 comprising in the present instance a centrifugal fan blower hav'uu; a i'enll'ully disposed intake 5 and a tangeutiuiiy dis- Specification of Letters Patent.

Patented Aug. 12, 1919.

Application filed December is. 1917. Seria1No.207,706.

. other gas heated apparatus. In the present instance I have shownin dotted lines in Fig. 2 a fragmentary portion of a furnace 8 to which the pipe 7 would lea/r soas to suppiy the eombustive mixture from the mixer to the burners (not shown) of the furnace.

Air and gas are delivered in the proper proportions to the mixer l by means of a mixing valve 9 of any suitable or preferred. (:UflHtlliL'tlOll. The particular mixing valve shown in the present instance simply for purpose of illustration. forms the subject matter of my eo'pending application Serial No. 204464, filed Novf 27. 191?. This valve attached to the intake 5 oi" the mixer is provided with an air iniet port on one side and :1 gas inlet (.Ullll('li( ll ll on the opposite side. the valve proper disposed within the (using being constructed to open and close the air and gas inlet ports equally and si1uultanvously upon rotative movement of the valve within the raising by means of an arm 12 rigidly mounted roaXially with the valve. The relative proportions of air and gas may be varied as om-asion requires. l) adjusting the valve linigitiulinally in the (:1S ing. which adjustment, however. does nol interfere with [he rotative openiu and (dosing movements of the valve.

The mixing: valve is housed in a suitable easing shaped to provide a vylindricul valve chandler Iii; provided with an air iulol port 237 and a gas inlet port 38 nrrzu-iged in this instance at lliair-ietrii-ully opposite sides of the chamber. The mixing valve l:- (:unmutteil through means of the coupling; stud 39 to the intake 5 of the mixer so that by means of suction therefrom nil and gas will he drawn through the ports 37 and 2 into the valve chamber and thenve to the mixer through the passage 41. The valve designated generally by reference character fits within the evliudrirnl i-hamher 36 and capable of living osriliated and moved longitudinnllv therein for purposes of ad adapted to register with the port 37 and at its opposite side with a port 44 adapted to register with the port 38.

An arcuate wall 4-5 disposed around and extending downwardly from the port 14 deflects the inflowing gas and provides a passage 46 through which the gas is drawn into the passage l1 where it is mixed with the air flowing in through the ports 37 and 43. The top of the valve body {2 is provided with an upwardly projectlng boss 47 to which the operating handle 12 is fixedly secured by a set screw 51. By means of this handle the valve body may be oscillated between fully open position, in "which a lug 52 projecting downwardly from the handle 12 en ages a fixed stop 53, on the casing and an a justahle abutment 54 consisting of a setscrew threaded through a boss 50 located degrees from the boss and locked in adjusted position by a lock nut. 'When the handle is in the position shown in Figs. 2 and 3 the ports 43 and 4-1 are in full registration with their respective ports 37 and 38. When the handle is swung until the boss 52 engages the adjustable sto 54 the ports 43 and -14 are both in only slight registration with their respective inlet ports, 50 that onlv a small uantit-y of air and gas will be ad mitted. his construction prohibits the entire closing off of the air and gas, thereby insuring a flow to the mixer 4 and the burners at a rate in excess of the rate of flame travel and eonsequentl eliminating all danger of flareback from t e burners.

Different grades of gas or different purposes for which the apparatus-is to he employed may require a variation in the [elative proportions of air and gas included in the mixture. and I have therefore made provision for regulating the relative proportions of air and gas delivered to the mixer, consisting of an adjustable set screw 55 threaded downwardly through the horizontally projecting portion of the boss 47 into engagement with a supporting bar 56 which is tixcd to the top of the casing and )rojccts directly beneath the screw 5."). By at justin this screw in one direction the valve will be moved lengthwise to incr'asc the dicetive area of the port 44 and diminish that of the port 43. and when adjusted in the o posite direction will effect an inverse action. Thus the relative proportions of air and gas admitted to the mixeronay hcregulated and controllml to a fine dcgrcc of nicety. and it should he noted thatthis regulation of the proportions atl'ects in no way the opening or closing of the valve by means of the handle 12.

Gas is supplied to my apparatus from the city main through a lead pipe 13 which is connected with one side of a pressure-reducing regulator H, the other side of the regulator being connected through a pipe 15 with a mixing valve 9. The pressure reducing device comprises a valve 16, the stem of which is attached to a diaphragm 17, the weight of the valve and stem being supported by a small contractile spring is attached at its upper end to a screw or plan 19 adjustably threaded through the top 0? the regulator casing. The valve 16 is normally closed, but when suction is created through the pipe 15' by the mixer -l this suetion will be transmitted through the lead passage 21 to the chamber beneath the diaphragm 17, thus lowering the diaphragm and opening the valve 16 so as to permit aflow of gas at substantially atmospheric pressure. This pressure reducing regulator delivers gas at uniform and substantially at-mos heric pressure to the mixer irrespective o the pressure or variations in the pressure of the as in the lead pipe 13. The mechanism tins far described constitutes the subject matter of other applications, and so far as the principle of my present invention is concerned these mechanisms may be of materially different construction than those herein shown for purposes merely of illustration.

My improvements. which will now be described. pertain to apparatus for automatically actuating the arm 12 so as to open or close'the mixing valve 9 as more or less heat is required at the burners. thereby automatically regulating the amount of air and gas delivered to the mixer so as to maintain a uniform and requisite temperature in the apparatus heated by the combnstive mixture delivered to the burners.

From the high pressure side of the pressure reducing regulator. I have run a bypass pipe 22. which as shown. is connected at one end with the pipe 13 and at its other end is connected with the intake to the mixing valve at the low pressure side of the pressurereducing regulator. In the pipe 22 l have provided a restriction which gives an aperture 23 of predetermined size which will permit a relatively small flow of gas. for instance 10 feet per hour. from the high to the low side of the pressure reducing ,rcgulator Normally this gas tiows throu h the b v-pass pipe :12 and is dclivcrcd into t 1e mixing valve with the gas flowing through the reducer past the valve 16. The pipe :22 i'xtcnds into proximity to the furnace. boilcr or other apparatus S. the tcmpcraturc of which is to be control led. and in this instance I have interposed a shut-oh valve :24 which is automatically opened and closed as the tcmpcraturc in the apparatus 8 falls below or rises above the temperature required. In the present instance this valvc :24 is con trolled by the thermostatic clcmcnt '25 projecting into the furnace. but it should he understood that a pressure controlled clcmcnt might be substituted for the thermostatic clement 25 without all'ccting the principle of my invention. In other words, if the apparatus 8 is a furnace or forge, a thermostatic element would be employed, while if the apparatus is used in conjunction with a bollerof either high or low pressure type the valve 24 would be opened and closed by a steam pressure actuated element oi well known or preferred construe tion. In eitherevent, the actuation and control of the mixing value is secured by automatic opening or closing of the shut-ofi valve 24.

From the pipe 22 between the restriction 12.; nd the valve '24 I lead a pipe 26 which is connected at its other end with a diaphragm receptacle 27, the connection with the receptacle being established below the diaphragm 28. Fixedly secured to the center of the diaphragm and projecting up \vardly above the receptacle 27 is a rod or plunger 29, which in turn is connected with the mixing valve arm 12 through the intcrincdiury of a flexible connection 31, such as a chain which is trained over a pulley at the top of the post 33 and is eouipped with a counter-balance weight 34. Normally when the temperature or pressure in the apparatusS is below that required to shut oil the valve 24, the diaphragm '28 will assume its lowered position shown in full lines in Fig. 2 and the arm 12 will be drawn upwardly into the full line position shown in this figure, so that the mixing valve is open to deliver a predetermined quantity of air and gas to the mixer. \Vhen the temperature or pressure in the apparatus 8 rises sufficiently to close the valve 24, the gas under pressure flowing past the restriction will flow through the pipe 26 into the receptacle 27 where it will accumulate and act against the diaphragm 28 and elevate this diaphragm, thereby pcrmittingthe arm 12,

which if preferred, may be weighted near its outer end, to giving downwardly under gravity lo the dotted line position shown in Fig. 2. thereby reducing the amount of air and gas permitted to enter the mixer and consequently reducing the amount. of comhustive mixture delivered to the burners, so that the temperature of the apparatus 8 will la lowered. Upon lowering of the temperalurc the valve 24 will again open so as to relieve the pressure in pipe 26, whereupon the diaphragm 28 will lower under gravity forcing out the accumulated gas beneath it and swing the arm 12 upwardly again so as to open the mix ing valve and admit a larger quantity of air and gas. It willthus be manifest that the pressure of the gas from the city main is utilized as a motive force to regulate the admission of air and gas through the mixing valve'and that by means of this construt-lion the temperature or pressure as the "he pipe 22 and the case may he, in the apparatus 8 to be controlled is automatically regulated to a line degree of niccty.

It should he understood that the particular type of automatically actuated valve 24 employed is immaterial so far as the principle of my present invention is concerned as are also the particular construction of the mixer and the pressure reducing regulator My invention, however, resides in the combination of various elements which enable me to utilize the gas under pressure for the purpose of automatically regulating the amount of combustive mixture delivered to the burners, and therefore I am enabled by this invention to automatically maintain any desired and a substantially uniform temper: ature or pressure in, the apparatus 8 which is to be controlled.

I claim:

1. In an apparatus of the character described, the combination of an air and gas mixing device a gas pressure reducer, a bypass pipe leading fro l the high pressure to the low pressure site of said reducer, an automatically controlled valve in said pipe, and means controlled by theopening and closing movements of said valve for increasing or diminishing the flow of mixture to said mixing device.

2. In an apparatus of the character de scribed, the combination of an air and gas mixing device, a gas pressure reducer, a. by pass pipe from the high to low side of said reducer, automatically controlled means for var ing the pressure in said by-pass pipe,

and means controlled by said fpressure forincreasingor diminishing the ow of mix to re to said mixing device.

3. In an apparatus of the character described, the combination of an air and gas mixing valve, a gas pressure reducer, a by pass pipe connected with the gas supply pipe and parallel with said reducer, an automatically controlled valve disposed in said by pass pipe, a pressure actuated apparatus, a connection between said apparatus and said icy-pass pipe, and a connection between said apparatus and said mixing valve whereby said mixing valve is opened or closed as the automatically controlled valve in the bypass ipe is opened or closed respectively.

4. In an apparatus of the character described, the combination of a gas supply pipe, a pressure reducing regulator inter posed therein, an air and gas mixing valve connected to said pipe a by-pass pipe connected at one end to said gas supply pipe at the high pressure side of the pressure regulator and at its other end to the mixing valve and provided with a restriction, an

automatically actuated valve disposed in' said by-pass pipe, a pipe connected at one end intermediate said restriction and solid valve, :1 pressure actuated device connected with the other end of said pipe, and operative connections between sand pressure aetn- "ted device and said mixing- \nlre.

5. In an apparatus of the character descri bed. the combination of n mixing valve, :1 gas pressure reducer connected to the in take end of said valve, :1 by-pass around said rednwr, pressure actuated means f0r.0peningmr closing suit] mixing, valve, and auton'mtivnlly operated means in said bypass fur regulating the pressure whereby said pressure net'naiing means is operated.

GARNET W. MCKEE. 

